It depends, I had a group of 31+ that did it 3rd try and in 2 portals. Yet I had a group of a 29, a few 30s and 31s and it was 2hours+ of wipes on Atheon because they had trouble with oracles (like wtf?), I had to drop relic to help them then pick it back up and repeat (as you said you do no more damage above level 30; excluding abilities, those do more, so I was VERY -blam!-ing confused as to why they had problems). TLDR; I've had bad experiences with 29s and 30s in HM VoG. But I do try and help them when I can (be it I'm wasting my time often). Edit: Personally I don't know how people even manage to -blam!- up on VoG, supplicant explodes or a bug then sure but in reality both should be rare occurences and it should take 3 tries max.